Private Equity: What It Is, How It Works, and Who Invests

You’ve probably heard the term tossed around in finance news or maybe when a company you know gets bought out. But private equity isn’t just a Wall Street buzzword — it’s a massive, concentrated ownership model that reshapes companies, jobs, and entire industries.

Global private equity assets under management (2024): $8.2 trillion ·
Average holding period for a PE-backed company: 5–7 years ·
Number of active private equity firms worldwide: over 5,000 ·
Typical minimum investment for an individual in a PE fund: $25 million ·
Share of U.S. workforce employed by PE-owned companies: approximately 12%

Here are the essential facts that define the private equity landscape.

What exactly does private equity do?

How private equity firms raise capital

• Private equity firms pool capital from institutional investors like pension funds, endowments, and insurance companies, as well as high-net-worth individuals (Investopedia’s private equity definition).
• Fund managers — called general partners (GPs) — raise money from limited partners (LPs) and invest it through a fund with a fixed lifespan, typically 10 years (Carta’s private equity guide).
• LPs commit capital upfront but only send money as deals are identified — a structure called “capital call” that prevents idle cash.

The pattern: PE firms don’t invest their own money. They act as general partners who deploy other people’s capital, taking a cut of profits in return.

How PE firms acquire and manage companies

• The core acquisition model is the leveraged buyout (LBO), where debt finances a significant portion of the purchase price (Carta’s private equity guide).
• Once acquired, the portfolio company becomes a platform for value creation: strengthening management, acquiring add-on businesses, launching new products, and streamlining operations (KKR’s official explainer).
• PE investors often recruit their own senior teams — a Harvard Business School study found that almost 58% of PE investors install new leadership (Harvard Business School working paper).

Why this matters: The same Harvard study found that more than 85% of PE investors adjust their target IRRs for firm riskiness, showing that risk calibration is central to the model.

How PE firms exit investments

• PE firms aim to sell portfolio companies within 5–7 years through one of three routes: a sale to another firm (secondary buyout), an initial public offering (IPO), or a recapitalization.
• The holding period is driven by the fund’s 10-year life: most value creation must happen in the first half of the fund so the exit occurs before the fund winds down.
• Exits are the moment when returns crystallize — until then, paper gains are unrealized and LPs cannot redeem their capital.

The implication: Every PE investment is a timed gamble. If market conditions sour during the targeted exit window, firms may hold positions longer or accept lower returns — but their LPs have no easy way to pull out.

What is private equity in simple terms?

Private equity vs. public stock market investing

• Private equity is ownership in companies not listed on public exchanges (Investopedia’s private equity definition).
• Unlike buying shares of Apple on the stock market, PE investors commit money for years and cannot easily sell their shares — the investment is illiquid by design.
• PE firms typically acquire a majority stake, giving them control over management and strategy, unlike minority public shareholders (Carta’s private equity guide).

The trade-off: In exchange for giving up liquidity, PE investors expect higher returns than public market investments — but those returns are not guaranteed.

The role of leverage in private equity

• Leverage — borrowed money — is a defining feature of LBOs, used to increase the size of acquisitions without committing more equity capital.
• The acquired company’s own cash flows and assets serve as collateral for the debt, meaning the portfolio company bears the repayment burden.
• While leverage boosts returns in successful deals, it also increases bankruptcy risk if the company cannot service its debt during downturns.

The pattern: Leverage is a double-edged sword. It enables PE firms to acquire larger companies than their equity alone would permit, but it also means the acquired company starts life with a debt load that can constrain investment.

Who are the big 4 PE firms?

Blackstone

• Blackstone is the largest alternative asset manager globally, with over $1.1 trillion in assets under management as of 2024.
• Founded in 1985 by Peter Peterson and Stephen Schwarzman, it has diversified into real estate, credit, and infrastructure beyond traditional PE.
• Blackstone’s PE business focuses on leveraged buyouts and growth equity across sectors like technology, healthcare, and financial services.

KKR

• KKR (Kohlberg Kravis Roberts & Co.) pioneered the leveraged buyout and is known for the landmark $31.4 billion takeover of RJR Nabisco in 1989.
• The firm manages over $500 billion in assets, with major PE investments in energy, technology, and consumer goods.
• KKR has expanded into private credit, infrastructure, and real estate through dedicated investment platforms.

Carlyle Group

• Carlyle Group was founded in 1987 and manages approximately $400 billion in assets across PE, credit, and real assets.
• The firm has a strong presence in aerospace, defense, and government services, and has historically been known for its political connections.
• Carlyle invests through multiple strategies including buyout, growth, and distressed assets.

Apollo Global Management

• Apollo Global Management manages about $600 billion in assets, with a particular focus on credit and distressed investing alongside traditional PE.
• Founded in 1990 by Leon Black, Joshua Harris, and Marc Rowan, Apollo is known for its “value-oriented” approach and insurance-related investment platforms.
• The firm’s PE arm targets control investments in industries such as financial services, manufacturing, and technology.

Why this matters: These four firms control a combined $2.6 trillion in assets — roughly one-third of the entire global PE industry’s $8.2 trillion AUM. Their investment decisions affect millions of workers across thousands of portfolio companies.

What is the dark side of private equity?

Job losses and wage cuts after PE buyouts

• Academic studies document that PE-owned companies often experience higher layoff rates and slower wage growth compared to similar firms without PE ownership.
• A well-known 2019 study by economists at the National Bureau of Economic Research found that PE buyouts lead to a 13% reduction in employment at target companies within two years.
• The effect is concentrated in industries with higher levels of debt and in companies where cost-cutting is the primary value-creation strategy.

The catch: Some portfolio companies grow employment after a buyout. The net effect on workers depends heavily on the PE firm’s strategy, the sector, and economic conditions — but the risk of job cuts is real and documented.

Increased debt burden on acquired companies

• Companies acquired through LBOs typically see their debt levels rise sharply, often exceeding 5–6 times EBITDA.
• High debt service costs can force companies to cut investments in R&D, equipment, and employee training to meet interest payments.
• During economic downturns, overleveraged portfolio companies are more likely to default or file for bankruptcy than comparable firms with lower debt.

Short-term profit focus vs. long-term company health

• PE firms operate on fund timelines of 7–10 years, incentivizing strategies that boost short-term profitability for a timely exit.
• Critics argue this pressure leads to underinvestment